Such devices have been used to propel skaters since the late 1800's as evidenced by U.S. Pat. No. 302,517 which issued to C. H. Nelson in 1884. This device consisted essentially of a large, generally rectangular sail, adapted to be secured to the body of the skater. The main mast and yards were formed in detachable sections to enable the device to be taken apart for ease of transportation. While the user, by manipulation of the lower half of the sail, has some degree of control on for example his speed, and could by body movement affect a change of direction, the device would be difficult to control in high wind situations in view of the large sail area, and since the sail was in fact strapped to the skaters back, the structure could not be collapsed sufficiently quickly to avoid an accident.
Numerous attempts were made to improve the skate sail concept and in 1932, S. A. Sprinkle designed a folding skate sail which became the subject of U.S. Pat. No. 1,859,178. This device took the general form of an isosceles triangle and consisted of a central vertical main mast and upper and intermediate sail bracing members extending transversally of the main mast, each of the aforesaid members being detachably secured to the main mast and to the sail to provide support therefore. Sprinkle, however, designed his device such that it is hand held and would be dimensionally small enough to enable the user to fold it to a size suitable to be placed in the pocket. Bearing this in mind, it is difficult to envisage such a device being capable of propelling the user at any high speed over ice and snow, as is claimed. Even if the components were enlarged to provide a sufficiently large sail area, the device would be difficult to control and thus dangerous. Furthermore, when utilizing this device on, for example, a straight race track, the prevailing wind conditions would make it extremely difficult for the user to return to the starting line after each race. The user is therefore faced with the inconvenience of having to take the device to pieces at the end of each race, and to reassemble same before the next race.
Finally, attention is drawn to U.S. Pat. No. 3,768,823 which issued in 1973 to Daniel E. Goldberg. The device according to this invention comprises a skate sail having a sectional mast and boom, each preferably made of three telescoping sections secured one to the other by a slotted male coupling telescopingly interfitting with the end portions of the mast and boom. Three jamb cleats are provided one at each end of the mast and one at the tail end of the boom. These cleats comprise an insert into the tubular aluminum alloy mast and boom on a wooden or plastic member having a jamb notch cut longitudinally therein and having a width sufficiently wider than the width of the halyard or lanyard line used to secure the sail and tapering to a width substantially less than the diameter of the line. Adjacent the narrow end of the jamb notch there is preferably a hole through which the line is passed with one end being secured to the cleat member by knotting the end of the line. The jib is curved and preferably made of three sections, and the tail bow is made of one flexible piece and is secured to the tail end of the boom by a lanyard.
It should be readily apparent from the above that this device is extremely complex in construction and some considerable effort is required in assembling the device to a useable condition. Apart from the relatively high manufacturing costs this device suffers the same disadvantages as the Sprinkle sail in that the device has to be completely taken to pieces for ease of transportation against the prevailing wind.